Sunflowers

If you look closely at the center of a sunflower you can see that the disk flowers grow in a mesmerizing pattern of two opposite spirals. This is most easily seen either before the disk flowers open up or after the seed has set and all the accessory flower parts have fallen off. This is one of the more interesting patterns in nature.
The rough-hairy quality of the Common Sunflower is characteristic of many members of its family. These little bristles probably serve two functions: to discourage plant-eating animals and to conserve water in the plant by limiting evaporation.
Members of the sunflower family are popular with butterflies because the wide flower head makes a good "landing platform" and the numerous individual flowers make for a high probability of finding nectar. Monarch butterflies are commonly seen nectaring on sunflowers during their fall migration.